Pharmacologically active cholinergic compositions, and methods for making same and use thereof in treating disease

ABSTRACT

Compounds useful as cholinergic drugs are disclosed which have the formula A--B and pharmaceutically acceptable salts thereof having the formula [(A--B)Q]+ q  M -q  wherein M is a pharmaceutically acceptable anion, Q is a proton or lower alkylating group, q is as integer from 1 to 3, A is a saturated or unsaturated five- or six-membered heterocyclic moiety and B is a saturated or unsaturated five-memebered heterocyclic moiety wherein R 1  and R 2  are each independently hydrogen, halo, branched or straight-chain C 1  -C 6  alkyl, branched or straight-chain C 1  -C 6  haloalkyl, branched or straight-chain C 1  -C 6  alkoxy, hydroxyl, keto or aryl; Y is --N═ or ##STR1## Z is --N═, ##STR2## --O--, --S--, ##STR3## and R 3 , R 4  and R 5  are each independently H, lower alkyl or aryl; W is --O--, --N═, or --S--; m is an integer from 1 to 5; n is an integer from 0 to 7; p is 0 or 1; and wherein, on a given molecule, when m is 2, or more, the R 1  &#39;s can be the same or different and two R 1  &#39;s can form a carbocyclic or heterocylic moiety fused onto adjacent positions of A and when p is 1, the two W&#39;s can be the same or different; and when n is 2 or more, the R 2  &#39;s can be the same or different and two R 2  &#39;s can form a carbocyclic or heterocyclic moiety fused onto adjacent positions of B. Pharmaceutical compositions useful in treating disorders of the central and peripheral nervous system of mammals, comprising an effective amounts of the aforesaid compounds, can be administered orally or intravenously.

BACKGROUND OF THE INVENTION

1. Technical Field

This invention relates to novel chemical compounds useful as cholinergicdrugs, processes for preparing and pharmaceutical compositionscontaining such compounds, and methods for using them in the treatmentof disease.

The invention further relates to novel compounds which act oncholinergic receptors of the central and peripheral nervous system. Moreparticularly, it relates to certain compounds which are selectiveagonists and antagonists for subtypes of muscarinic cholinergicreceptors, to processes for the preparation of such compounds, and topharmaceutical compositions comprising them which can be usedtherapeutically for the treatment of diseases and disorders associatedwith such receptors in humans and animals.

2. Description of Background Art

Muscarinic pharmacological behavior was first distinguished from itsnicotinic cholinergic counterpart by Dale in J. Parmacol. Exper. Ther.,6, 147-90 (1914). As used herein, the term "muscarinic cholinergicreceptors" denotes that class of cholinergic receptors which areactivated by acetylcholine and also by the alkaloid muscarine. Compoundssuch as muscarine which activate muscarinic receptors, in addition tobinding strongly to them, are termed muscarinic "agonists" or muscarinic"cholinomimetics". Certain chemical compounds such as atropine bind tomuscarinic cholinergic receptors but do not lead to a pharmacologicalresponse and, in fact, block the effects of acetylcholine and muscarinicagonists; they are termed muscarinic cholinergic "antagonists" or"cholinolytics". Finally, some compounds have less pharmacologicalpotency than so-called "full" muscarinic agonists (i.e., those with unitintrinsic activity); they are termed "partial agonists". Muscarinicreceptors are located on the smooth muscle and glands which theyinnervate. They are also found in ganglia and between neuronal synapses,and are generally located post-synaptically and/or pre-synaptically.Muscarinic cholinergic receptors can be visualized usingradioactively-labeled muscarinic agonists or antagonists.

Heretofore, there has been much discussion in the neurosciencesliterature on muscarinic receptor subtypes analogous to alpha and betaadrenergic receptor subtypes and histamine H1 and H2 subtypes.Classification of muscarinic receptors into two subtypes, M₁ and M₂, hasbeen proposed by Goyal and Rattan based upon the differentiating effectsof partially selective agonists NcN-A343 and bethanechol on the onehand, and the partially-selective antagonists pirenzepine and DAMP onthe other. See Goyal et al., Gastroenterology, 74, 598-618 (1978).According to animal assay, M₁ -activating behavior is associated withrelaxation of the lower esophageal sphincter of an anaesthetizedopossum; M₂ -activating behavior is associated with contraction of thelower esophageal sphincter. This unique model has served well in theidentification and localization of receptor subtypes of neurohormonalsubstances. See Goyal et al., supra, and Rattan et al., J. Pharmacol.Exper. Ther.m 224, 391-7 (1983).

Accordingly, it is an object of the present invention to providechemical compounds which are highly selective agonists and antagonistsfor muscarinic receptor subtypes, and which are useful for clinicalapplications in the treatment of memory and cognitive disordersincluding such senile dementias as Alzheimer's disease, problems ofgastrointestinal motility and secretion, cardiovascular problems andother disease conditions arising from and/or related to muscariniccholinergic function or disfunction. The invention is also intended toprovide chemical compounds which enhance and promote mental functionssuch as memory and coordination among healthy people. Yet another objectis to provide methods for preparing the aforesaid compounds,pharmaceutical compositions containing them and procedures foradministering the compounds to patients afflicted with theaforementioned disorders.

SUMMARY OF THE INVENTION

The foregoing objects are achieved according to the present invention bynovel compositions of matter which are compounds having the generalformula A--B, and pharmaceutically acceptable salts thereof having thegeneral formula [(A--B)Q]⁺ _(q) M^(-q). In these formulas, M is apharmaceutically acceptable anion, Q is a proton or alkylating group, qis an integer from 1 to 3, A is a saturated or unsaturated five- orsix-membered heterocyclic moiety having the formula: ##STR4## and B is asaturated or unsaturated five-membered heterocyclic moiety having theformula: ##STR5## wherein

R¹ and R² are each independently, halo (e.g., fluoro, chloro, bromo andiodo), branched or straight-chain C₁ -C₆ alkyl (e.g., metyl, ethyl,propyl, isopropyl, butyl, isobutyl, amyl, isoamyl and hexyl), branchedor straight-chain C₁ -C₆ haloalkyl, branched or straight-chain C₁ -C₆alkoxy, hydroxyl, keto or aryl (e.g., meta-chlorophenyl);

Y is --N═ or ##STR6## Z is --N═, ##STR7## --O--, --S--, or ##STR8## andR³, R⁴ and R⁵ are each independently hydrogen, lower (i.e., branched orstraight-chain C₁ -C₆) alkyl or aryl (e.g., meta-chlorophenyl); W is--O--, --N═ or --S--; m is an integer from 0 to 5; n is an integer from0 to 7; and p is 0 to 1. On a given molecule, when m is 2 or more, theR¹ 's can be the same or different and two R¹ 's can form a carbocylicor heterocyclic moiety fused onto adjacent positions of A; when p is 1,the two W's can be the same or different; and when n is 2 or more, theR² 's can be the same or different and two R² 's can form a carbocyclicor heterocyclic moiety fused onto adjacent positions of B.Pharmaceutically acceptable salts, [(A--B)Q]⁺ _(q) M^(-q), include acidand quaternary salts derived from the above wherein

Y is ##STR9## and Z is a neutral moiety, or wherein Y is a neutralmoiety and Z is ##STR10## The moieties A and B are joined to each otherby a single covalent bond so that the formula A--B becomes ##STR11## andthe formula [(A--B)Q]⁺ _(q) M^(-q) becomes ##STR12##

Among the moieties which A represents, the following are preferred:##STR13## wherein Z is --O--, --N═, ##STR14## and R¹, R³, R⁴ and R⁵ areindependently H or lower alkyl. When Q is H, the compounds are acidsalts; when Q is lower alkyl, the compounds are quaternary salts.

Among the moieties which B represents, the following are preferred:##STR15##

Optical (R and S) and diastereoisomers arising from chiral centers onthe compounds, and racemates and mixtures thereof are within the scopeof the invention.

Especially preferred among the compounds having the formulas A--B and[(A--B)Q]⁺ _(q) M^(-q) are the following: ##STR16## wherein R² ishydrogen or methyl.

The term "pharmaceutically acceptable salts" as used herein includesaddition salts of strong or weak acids and hydrates thereof which arephysiologically safe in mammals. Strong acids which formpharmaceutically acceptable salts with the foregoing compounds include,without limitation, hydrochloric, hydrobromic, hydroiodic, sulfuric andphosphoric acids. Weak acids which form pharmaceutically acceptablesalts with the foregoing compounds include, without limitation, citric,tartaric, malic, fumaric and/or maleic acids. Pharmaceuticallyacceptable salts of the compounds of the invention may exist inanhydrous form as well as in solvated, including hydrated forms. Ingeneral, the hydrated forms and the solvated forms in pharmaceuticallyacceptable solvents are equivalent to the anhydrous or unsolvated formfor the purposes of the invention.

The compounds according to invention can be prepared by severalsynthetic methods. One approach involves the following sequence ofreactions: ##STR17## wherein R¹ is alkyl or aryl; Q is alkyl; R³ isalkyl; and the halide can, if desired, be exchanged for a differentpharmaceutically acceptable anion to give a salt of formula [(A--B)Q]⁺_(q) M^(-q).

The B-CHO reactant can be prepared according to the following exemplaryprocedures: ##STR18## See M. E. Alonso et al., J. Heterocycl. Chem.,17,721 (1980) ##STR19## The two diastereoisomers can be separated byHPLC or column chromatography. The configuration at the carbon to whichthe aldehyde is attached is determined by the choice of d or l mannitol.

Another approach involves the following synthesis which is based uponthe disclosure in Kempter et al., J. Prakt. Chem., 313, 977-85 (1971):##STR20##

Schulman et al., J. Med. Chem., 26, 817-23 (1983) describes a model(hereafter, "the model") of the binding of acetylcholine to muscarinicreceptors. The model suggests that muscarinic agonists bind withmuscarinic receptors in a conformational arrangement which enables theagonist cationic head group to interact with an anionic receptor locusalong the local three-fold C(alpha)-N axis of the head group. Suchbinding action has since become known as "A-face approach". According tothe model, the ether oxygen (i.e., the alcoholic oxygen of esters suchas acetylcholine itself) simultaneously or soon thereafter interactswith a receptor site located approximately 1.2 angstroms from thatoxygen. Also, several new geometric parameters, viz, a dihedral angle,PNOQ, and a distance, PQ, were defined. When the energetics of theconformation of various semi-rigid muscarinic agonists possessing aNCCOC backbone were subjected to analysis by a combination of molecularmechanics and ab initio quantum mechanical methods, it became possibleto define the active conformations of acetylcholine and other muscariniccholinergic agonists. During that period, it was suggested by Gieren andKokkinidis in Trends Pharmacol. Sci., 5, 369-70 ( 1984) that thecationic head group would interact with the receptor anionic site alonga direction known as a "B-face". In that same publication, Schulman, etal., op. cit., 5, 75 (1984) pointed out that while the "B-face" approachwas possible, the active conformations deduced assuming an A-faceapproach would, nonetheless, still hold. With both the A-face and B-faceapproaches in mind, one of the present inventors turned his attention tothe muscarinic agonist pilocarpine, a plant-derived alkaloid. Thisagonist is unique in having an imidazolium group as the cationic headgroup. On the basis of these considerations, a new class of agonists hasbeen designed which incorporate imidazolium-derived moieties or theiranalogs as the cationic part of the agonist and having suitable oxygenand terminal methyl-containing groups. One compound of particularinterest is the furyl-N-methylimidazolium salt (I) having the followingstructure: ##STR21##

The muscarinic agonists of the present invention are believed to havespecificity for muscarinic receptors of the M₁ subtype. Accordingly,they are useful for the therapy of senile dementia of theAlzheimer's-type. Without wishing to be bound by theory, it is believedthat M₁ muscarinic receptors which are located post-synaptically inAlzheimer's patients remain intact while their M₂ receptors, locatedpre-synaptically and associated functionally with regulating the releaseof acetylcholine, are impaired. Thus M₁ -selective agonists which mimicthe behavior of acetylcholine when given as drugs, could augment anyinsufficiency in acetylcholine due to too few normally functioningsynapses.

The compounds of the present invention which have M₁ properties (andalso, possibly, some nicotinic properties which are useful when blendingor fine-tuning of muscarinic and nicotinic properties is required) canbe formulated into drug compositions which can be administered to normalhumans with no known impairments in order to improve long and short-termmemory function and to facilitate the development and utilization ofacquired skills.

Administration of the pharmaceutical compositions of the invention canbe effective elsewhere in the body. For example, in the gastrointestinaltract the compounds should improve gastrointestinal propulsion andtherefore enhance esophageal, gastric, small bowel and colonicpropulsive activity. Such prokinetic functions are responsive to M₁receptor agonists. Therefore this agent may have therapeutic use indisorders of gastrointestinal transit. More generally, becausemuscarinic M₁ receptors are widely distributed in the body includingcardiovascular, pulmonary, genitourinary, musculoskeletal, and endocrinesystems, the compounds of the invention should be useful in treatingthose conditions where stimulation of M₁ muscarinic receptors willproduce desirable effects.

Pharmaceutical compositions according to the present invention areformulated to take advantage of the fact that herein describedcholinergic drugs are readily able to cross the blood-brain barrier soas to be effective upon the central nervous system when administeredorally or intravenously. In formulating the present pharmaceuticalcompositions, at least one of the aforesaid therapeutic compounds of theformula A--B is admixed with one or more pharmaceutical carriers orexcipients as may be appropriate for the desired mode of administration.For example, pharmaceutical compositions to be taken orally can be inthe form of tablets, capsules or elixirs wherein the carrier orexcipient can be milk sugar, starch or gelatin to name a few. Forintravenous application, the pharmaceutical compositions can beformulated to include for example, water or saline.

In formulating the pharmaceutical compositions of the invention, it isdesirable to formulate dosage units each being calculated to furnish afixed dosage of active ingredient(s). It is sufficient to formulate thecompositions so that the active ingredient(s) constitute an effectiveamount as determined in each case by the physician according toprocedures well known to those skilled in the art. Preferably, aneffective dose of the compounds of the invention ranges from 10⁻⁸mole/kg to 10-4 mole/kg when administered intravenously. For oraladministration, the corresponding dose ranges from 10⁻⁷ mole/kg to 10⁻⁴mole/kg. At these levels, and because of the selectivity of thecompounds of the invention, there are no toxicity or preclusive sideeffects.

DESCRIPTION OF PREFERRED EMBODIMENTS 3.1 Example 1 Preparation of1-(N-methyl)-5-(5'-methyl)2'-furyl)imidazole

A quantity of 5-methylfurfural was condensed with methylamine (as a 40%aqueous solution) by a Mannich-type reaction to give the correspondingmethylimine (5-methylfurfurylidene-N-methylimine), following theprocedure set forth in Emling et al., J. Am. Chem. Soc., 71, 703 (1949).In the present example, 11.65 g (0.15 mole) of a 40% solution ofmethylamine in water was placed in a 125 ml Erlenmeyer flask containinga magnetic stirring bar and cooled and stirred in an ice-water bath. Tothis was added 11.01 g (0.1 mole) of 5-methyl-2-furanecarboxyaldehydedropwise over a period of 6 minutes to keep the temperature between 15°and 20° C. After 4 minutes additional cooling and stirring, the ice bathwas removed and the amber mixture was then stirred at room temperaturefor thirty minutes (stoppered). The mixture was then re-cooled inice-water and solid KOH pellets (9.25 g) were added over a period offour minutes to keep the temperature below 15° C. During this time, alower aqueous layer and an amber upper organic layer were formed. Theaqueous layer was extracted twice with 20 ml portions of methylenechloride and the extracts were combined with the organic layer, driedover solid KOH pellets (ca. 16 g), and allowed to stand at ambienttemperature for one-half hour, and then concentrated under reducedpressure to give 12.08 g of brown oil. The following spectral data wereobtained: Proton NMR (EM360, 207 mg/0.4 ml deuterochloroform and TMS);delta=2.37, singlet, 3H; 3.5, singlet, 3H; 6.1 broad doublet (J ca. 4Hz), 1H; 6.63, broad doublet (J ca. 4 Hz), 1H; 8.03, doublet (J ca. 2Hz), 1H. IR spectrum (5% carbon tetrachloride), (4 minute scan): nopeaks above 3000 cm⁻¹ or 1680-1800 cm⁻¹ ; 2770(sharp), 1643(strong),1587, 1530, 1450, 1432, 1400, 1381, 1368, 1343, 1275, 1263, 1229, 1201,1124, 1020, 1002, 990, 968, 959, 953, 940, 662, 649 cm⁻¹ (0.1 mm cavitycells). Distillation of the clear amber mixture gave a major fractionboiling at 60.5° C. @ 9 mm Hg in the form of a clear colorless liquidwhich turned very slightly yellow in air. The next fraction boiledbetween 60.5 and 61.0° C. at 9 mm and was a clear, very faintly-yellowliquid. This fraction has essentially the same nmr spectrum as thatdescribed previously, and was used in the next step.

The methylimine described above was converted to1-(N-methyl)-5-(5'-methyl-2'-furyl)imidazole having the followingstructure: ##STR22## by reaction with p-toluenesulfonylmethylisocyanide(Tosmic) by the method taught in van Leusen et al., J. Org. Chem., 42,1153 (1977). In the present example, a solution containing 3.08 g (0.025mole) of the imine, 7.81 g (0.40 mol) of Tosmic, 6.91 g (0.05 mol) ofanhydrous potassium carbonate, 50 ml of methanol and 100 ml ofdimethoxyethane (glyme) was stirred magnetically for 17 hours in astoppered 250 ml Erlenmeyer flask. The mixture was decanted from thesolid potassium carbonate and evaporated to dryness under reducedpressure. A quantity (11.17 g) of brown-amber oil containing some solidwas obtained. Instead of the methanol/glyme solvent system, thesynthesis can be carried out using pyridine according to the method ofMiyashite et al., J. Org. Chem., 42, 3772 (1977).

EXAMPLE 2 Preparation of 1-(N-methyl)-5-(5'-methyl-2'-furyl)imidazole,Hydrochloride

A quantity, (10.11 g; 0.0821 mole) of the imine prepared in Example 1and a 20.00 g (0.1025 mole) of Tosmic were dissolved in 100 ml drypyridine and the solution was kept at room temperature for 10.5 days.The brown mixture was concentrated in a rotary evaporator under reducedpressure at 50° C. to give 18.58 g of a dark brown oil. The oil wasdissolved in about 50 ml of methylene chloride and extracted three timeswith 10% HCl. The combined HCl extracts were back-washed twice withmethylene chloride, then made basic with KOH pellets (with cooling). Thebasic mixture was extracted twice with 30-ml portions of methylenechloride. The combined extracts were dried over magnesium sulfate andconcentrated under reduced pressure to give 6.88 g of a dark brown oil,smelling somewhat of pyridine. This was dissolved in 25 ml of methylenechloride, cooled in ice and saturated with HCl gas to give thehydrochloride salt. A ten precipitate formed and part of the solidredissolved upon further HCl addition. The mixture was concentratedunder reduced pressure to give 4.82 g of additional solid which wascovered with about 30-50 ml methylene chloride, swirled andsuction-filtered. The residue, weighing 3.907 g after methylene chloriderinse and air-drying, was a pale greenish yellow powder. A quantity(2.001 g) was dissolved in and recrystallized from 10 ml hot absoluteethanol after filtering the solution through charcoal to a golden-yellowcolor; cooling to room temperature gave yellow needles. Suctionfiltration and air drying gave 0.454 g of yellow needles, mp 239°-241°C., dec.

The nmr (64 mg/0.5 ml D20, 60 MHz) showed: delta=2.45, S, 3H; 4.04, S,3H; 4.92 (NH or H₂ O); 6.30, d, J=3.5 Hz, 1H (slightly broadened); 6.80,d, J=3.5 Hz, 1H; 7.63, d, J=1.5 Hz, 1H, 8.80 s(br). Irradiation atdelta=2.45 converted the peak at 6.3 to a sharp doublet, J=3.5 Hz andalso sharpened the peak at delta=6.8. Irradiation at delta=4.04converted the peak at 8.80 to a sharp doublet, J=1.5 Hz, and alsosharpened the doublet at delta=7.63. The assignments are the following:The peaks at 6.30 and 6.80 are the ring protons on the furan ring, thepeak at 2.45 is the furan methyl group, the peaks at 7.63 and 8.80 arering protons on carbons of the imidazole ring, 4.04 corresponds to theimidazole methyl group and the peak at 4.92 is the NH proton. The peaksat 7.63 and 8.80 are similar to their counterparts in pilocarpine.

A quantity (370 mg) of the yellow crystalline needles prepared above wasredissolved in hot absolute ethanol, decolorized with charcoal, andrecrystallized to give 158 mg of pale yellow needles, mp 239°-240° C.,dec. This was vacuum-dried for 1.5 hours at room temperature. Thefollowing elemental analysis was obtained: %C, 54.74; %H, 5.65; %N,13.67; %Cl, 17.60. This is consistent with the following structure:##STR23##

EXAMPLE 3

The compound (I) obtained according to Example 2 was tested by assay onthe lower esophageal sphincter of an opossum anaesthetized with sodiumphenobarbitol. In carrying out the assay, the lower esophageal sphincterlocated between the esophagus and the stomach remains in a state oftonic contraction; therefore, a pressure sensing (manometric) catheterintroduced from the animal's mouth into the lumen monitors loweresophageal sphincter pressures by registering a sustained high pressurezone, due to the lumen's myogenic contraction which is independent ofneural or hormonal influences. Neural activity and hormones can increaseor decrease the sphincter pressure and both excitatory and inhibitoryinfluences can be readily detected.

The intraluminal pressures from the lower esophageal sphincter,esophageal body and the stomach are continuously monitored using a lowcompliance, waterfilled and continuously perfused catheter anchored inthe lower esophageal sphincter so that artifacts due to axial motion canbe minimized. See Goyal et al., Gastroenterology, 71, 62-7 (1976). Allanimals receive bilateral cervical vagotomy to eliminate vagallymediated changes in the sphincter pressure. Nerves to the sphincter arestimulated electrically by electrodes which are either applied to thedistal end of the cut vagus nerve or applied intramurally in thesphincter. See Goyal et al., supra, and Rattan et al., Am. J. Physiol.,234, E272-E276 (1978). Reflex relaxation of the sphincter is produced bydistension of the esophagus with an intraluminal balloon. Drugs areadministered in the arterial supply of the lower esophageal sphincter.This is done by opening the abdominal cavity and cannulating the arterythat leads to the lower esophageal sphincter. The compound is injectedinto the blood supply of the lower esophageal sphincter and its effecttherein is determined. The animal's vital signs are monitored and bloodpressure is maintained with intravenous infusion of saline. Some drugsare administered intravenously.

In summary, the above-described model permits identification ofmuscarinic agonists and antagonists in a physiological system.

According to this procedure, it was determined that the compound I hasonly M₁ effects, i.e., it acts on the M₁ receptors on the intramuralinhibitory neurons. Using this technique in the manner described below,it was found that compound I has a threshold dosage of 10⁻⁸ mole/kg anda peak effect at a dosage of 10⁻⁶ mole/kg. A micromolar solution gave80% of full agonist activity, indicating that it is a partial agonist.Its activity was found to be blocked by atropine. Compound I was testedon guinea-pig trachea and showed virtually no potency in contracting thetrachea muscle; this result is consistent with the fact that thosemuscles have essentially M₂ receptors whereas compound I is highlyselective for M₁ receptors.

The foregoing examples are intended to illustrate, without limitation,the compositions of the present invention, their preparation, and usethereof in treating disorders of the nervous system. It is understoodthat changes and variations can be made therein without departing fromthe scope of the invention as defined in the following claims.

We claim:
 1. Compounds useful as cholinergic drugs having the formulaA--B and pharmaceutically acceptable salts thereof having the formula[(A--B)Q]³⁰ _(q) M^(-q) wherein M is a pharmaceutically acceptableanion, Q is a proton or lower alkylating group, q is an integer from 1to 3, A is ##STR24## and B is ##STR25## wherein R¹ and R² are eachindependently hydrogen, halo, branched or straight-chain C₁ -C₆ alkyl,branched or straight-chain C₁ -C₆ haloalkyl, branched or straight-chainC₁ -C₆ alkoxy, hydroxyl, keto or aryl; and R³ is H, lower alkyl ormonocyclic aryl.
 2. Compounds according to claim 1 wherein R³ ishydrogen or lower alkyl.
 3. A compound according to claim 1 having theformula: ##STR26##
 4. A compound according to claim 1 having theformula: ##STR27##
 5. A compound according to claim 1 having theformula: ##STR28##
 6. A pharmaceutical composition useful in treatingdisorders of the central and peripheral nervous system of mammals,comprising an effective amount of a compound according to claim
 1. 7. Apharmaceutical composition according to claim 6, comprising an effectiveamount of a compound according to claim
 3. 8. A pharmaceuticalcomposition according to claim 6, comprising an effective amount of thecompound according to claim
 5. 9. A pharmaceutical composition accordingto claim 6, comprising an effective amount of the compound according toclaim
 6. 10. A method of treating disorders of the central andperipheral nervous system of mammals, comprising administering thereto apharmaceutical composition according to claim
 6. 11. A method accordingto claim 10, comprising administering a pharmaceutical compositionaccording to claim
 7. 12. A method according to claim 10, comprisingadministering a pharmaceutical composition according to claim
 8. 13. Amethod according to claim 10, comprising administering a pharmaceuticalcomposition according to claim
 9. 14. A process for producing compoundsuseful as cholinergic drugs, comprising the following sequence ofreactions: ##STR29## wherein B is as defined in claim 1.